Apparatus for delivering and receiving telephone messages



Jan 30, 1951 D. c. BEATTY APPARATUS EoR DELIVERING AND RECEIVING TELEPHONE MESSAGES Filed March 4, 1949 INVENTOR ATTORNEYS Patented Jan. 30, 1951 UNITED STATES PATENT OFFICE APPARAfrUsFoR DELIVERING AND RECEIV- ING TELEPHONE MESSAGES.

7 Claims.

l 1 This invention relates to improved electrical apparatus for delivering a message to a party calling an unattended telephone and for receiv,

ing, after such message has been delivered, any message which the calling party may desire to leave.

In my Cpending patent application Serial Number 40,248, filed July 23, 1948, now Patent No. 2,525,763, granted October 17, 1950, an apparatus for the same purpose is described. The main purpose of the present invention is to provide an improved circuit for such an apparatus, and to include therein means for automatically opening said circuit to turn off the apparatus when it has vdischarged its function on a specific occasion of use.

With the foregoing and other objects in View which will appear as the description proceeds, the invention consists of certain novel details of construction and combinations of parts, hereinafter more fully described and pointed out in the claims, it being understood that changes may be made in the construction and arrangement of parts without departing from the spirit o f the invention as claimed.

Referring to the drawing Figure 1 is a schematic View of apparatus constructed in accordance with the invention.

Figure 2 is a schematic View of a modification.

Figure 3 is a schematic view of a sound controlled relay and its connections with the control circuit.

Referring to the drawing in detail, 5 and 6 are leads connected directly to the ordinary telephone circuit including a telephone instrument, not

shown, and its signal device, also not shown.

When the telephone is attended, manually operated switch 1 is left open. During these periods Athe apparatus of the invention is out of use, and

:ordinary use of the telephone is made. When, however, the telephone instrument is to be left unattended, switch 'I is manually closed so that when calls are made to the unattended instrument, the apparatus will operate in a manner to be described.

Extending from telephone lead 6 is a lead 8 to -a relay 9 from which extends lead Iii in which is located the normally closed switch contacts II When relay 9 is energized, it will close contacts I2 and contacts I3.

From the description so far provided, it will be seen that with the telephone instrument unat- "f tended and switch I closed, a call placed to the telephone will, on the iirst surge of the intermittent ringing current, energize the relay 9 so as to momentarily close contacts I2 and I3,

Plugged into the ordinary house or other local electric supply are the leads I4 and I5. A manually operated switch I6 is located in the lead-I4.

Leads IB and I5 are connected to the terminals of the primary winding of a power transformer I'I.

Connected to one of the terminals of the secondary winding of the power transformer is lead I8. It may be noted, therefore, that when relay '9 is momentarily energized, a circuit will be closed as follows: lead IS, lead I9, holding relay 2B, lead ZI, closed contacts I2, leads 22 and 23, and back to power transformer I'l.

' When holding relay 2li is so energized, it will stay energized, even though contacts I2 irnmediately open under the intermittent energizing and ile-,energizing of relay 9 caused by the intermittcnt characteristic of the ringing current. Holding relay 20 will stay energized because it will have closed contacts 24, 25, The closing of contacts 24 places a short across the contacts I2 so that the current for energizing holding relay 2!) passes from lead 2I not through the contacts I2, but through lead 2E, closed contacts 24, lead 23, and back to power transformer.

The momentary closing of contacts I3, meanwhile, imposes an intermittent short circuit across telephone leads 5 and 6 as follows: from lead 6, through lead 26', closed contacts I3, lead 2l, lead 28, closed contacts 25, lead 29, and telephone lead 5. This causes a cessation of the intermittent ringing current.

As a result, a sustaining current is stabilized in the telephone circuit, much as is used for ordinary telephone conversation. This stabilized sustaining current condition will persist in the telephone circuit until it is interrupted following full use of the apparatus. This sustaining current is now closed through to one winding of a coupling transformer 3Q. Lead 28 is connected to one post-of said winding, with a blocking condenser 3I being located adjacent to and being connected in series between said lead and winding. Telephone lead 6 is connected to the other post, with a blocking condenser 32 being located adjacent to and being connected in series between said lead and said winding.

The closing through of the electrical circuit to one side of the coupling transformer 36 may be traced as follows: telephone lead 6, blocking condenser 32, coupling transiormer 3B, blocking condenser 3|, lead 28, contacts 25, lead 29, telephone lead 5.

In circuit with the holding relay 25 is a relay 33. This is a slow acting relay, of the type that is activated following a predetermined period of time after an electrical circuit is completed to and through its field winding. Accordingly, after said period of time has elapsed, the slow acting relay 33 goes into operation. This closes a circuit to a relay 34 as follows: from secondary winding of power transformer Si, through lead i8, lead I'S, lead 35, relay 3a, lead 35, lead 3l, closed contacts 38, leads 2i and 2S, closed contacts 2t, lead 23, and back to power transformer.

At this point, it may be noted that provide a reactance coil 39. This impedance is shunted across leads and 5 upon the closing of contacts 25.

The purpose of this isA to permit the operation ofmessage counting devices, not shown, and the operation of devices in coin-operated telephone instruments, also not shown, which through their operation deposit an inserted coin in its proper receptacle, rather than return it to the depositor as would be the case if such an electrical loadingv of the automatic switching circuit was not present. It is found desirab'ie to use such an impedance in the circuit to permit the operation of such message registers and coin-operated devices, where blocking condensers such as 3l, 32, are used in series with leads to the coupling transformer Si? as shown. Blocking condensers 3|, 32, in turn, being in series with the leads 25 and G, serve the function of preventing the passage of the sustaining direct current from the telephone leads to and through one winding of the coupling transformer. Likewise, these condensers permit transfer' of sound impulses with .greater fidelity.

I In the intermittent ringing circuit hereinbefore described is the condenser de, and energizing of the relay 35i will open the contacts H and close contacts iii This places a short circuit across the condenser 25, dissipates the stored-up electrical charge in the condenser created by the intermittent ringing current, and opens the closed electrical ringing circuit created by lead 6, lead 8, relay 9, lead i0, contacts il, condenser '45, and -lead 5.

When the slow acting relay 33 was energized, it also closed normally opened contacts e2. lThese contacts control electrical circuits for powering the -recording or input section of a suitable recording device, not shown; or the play-back or output section of said recording device. t is desirable of course that a circuit be c'osed through the output section of the recording device for the purpose of sending sound impulses from the recording device out through the telephone leads 5 and G-in other words, for the purpose of delivering a previously recorded message to a calling party.

Similarly, it is desirable that a crcuit be closed through the recording or input section of the recording device for the purpose of permitting 'sound impulses to be sent from the telephone leads 5, to the recording device for the purpose of recording a message being delivered by the `calling party.

The circuit for powering the recording or input "section of the recording device is as fol'ows: house supply lead I5, lead plug receptacle 44 having posts l5 and adapted for electrical connection to the recording or input circuit of the recording device, not shown, contacts lil, lead 48, contacts 42, lead 49, and out through house supply lead l5.

The circuit for powering the output or playback section oi the recording device is the same as that traced immediately above except that plug receptacle 55 having posts 5i and 52 electrically connected to the output section of the recording device is substituted for p ug receptacle 44, and contacts 53 are substituted vfor contacts (il.

The switching between circuits is accomplished by single pole, double throw switch 5d controlled by a relay 55. When relay 55 is not energized, contacts 47 are closed to operate the input section of the recorder. When relay 55 is energized, contacts 53 are closed to operate the output or play-back section of the recorder.

Leads 56, 51, 58 are connected to the recording device and through these sound impulses are transmitted between the recording device and the telephone leads 5, '5. Lead 5B is a common lead which is in circuit between the telephone circuit andthe recording device whether sound impulses are being delivered by the recording device, or are being received by the recording device. Lead 5% is used for transmitting sound impulses from the recording device to the telephone leads; lead 51 is used for transmitting sound impulses in the other direction, from the telephone leads to the recording device.

Lead 53 being a common lead, it is constantly in circuit with one side of the secondary winding of the coupling transformer 33. A single pole, double throw switch 59, however, is v'controlled by a relay Gil for the purpose of closing either contacts 5l or 62 so as to bring into the circuit either lead 56 or lead 5l.

In this connection, relays 55 and '65 will both have been energized at the time the slow acting relay 33 was energized. This is by reason of the fact that the slow acting -'relay ,33 will have closed contacts 33. Therefore, a circuit will have been closed as follows: lead i8, normally closed contacts 63, lead 64, lead normally closed switch 66, relays 55 and '65, lead 6l, leadti, lead 3i, contacts 38, lead 2i, lead 2.5 contacts 2li, 'and lead 23A back` to the power transformer.

Therefore., it will be seen 'that relays' 55 and 6! having been energzed'alt the time stated, the contacts l53 to the output vsection of the recorder will be closed, and contacts 62 will also be closed, bringing into the recorder output circuit the leads 5B, 58 for the .purpose of de ivering the output to the telephone leads 5, 5. in'otheriwo'rds, when the calling party places lhis call, .a short time interval will transpire `'from the Itime the first ring is made on the instrumen-t, this time interval .being that required for a'ctivaticn of the slow acting relay 33. After this time interval, the

.previously recorded message lefton the recording corder, and the calling .partyfdelivers his message over the leads 5l, 58 which will nowbeelectrically connected through the vcoupling vtransformer to the telephone leads V5 and 6.

y Means is provided .for the :purpose of causing al1 circuits to open after full operation of "the aerien-e I provide a means iorenergizing the relay 69 at the desired time. To this end, a relay 'l0 has leads Il and 'l2 respectively connected to lead 28 that extends to the telephone lead 5, and to tele.- phone lead ti. Therefore, relay 1B Will have been energized on stabilization of a sustaining current in the telephone circuit, and therefore will open and hold open throughout the use of the apparatus the contacts 13. 'With thesecontacts 13 open, the cut oi relay 69 cannot be energized.

I propose, in this connection, to control the vrelay I0 in any of various ways.

For example, relay 'IIJ can be controlled by a slow acting type of relay; an electrical time control device; or a voice or sound controlled relay which will stay in an operative position for a predetermined period of time following the cessation of a current carrying voice or sound impulses in an electrical circuit, and which will move to an inoperative position at the end of said predetermined period of time.

With respect to this last, said voice controlled relay, not shown, would be placed at any suitable location inthe telephone sustaining circuit in or the contacts I4 of Fig. 2. Utilizing the cone nections illustrated in Fig. 3, the leadsll and 1.2 of Figs. 1 or 2 would be eliminated. In Fig. 3, a relay 15 is a high resistance, fast release type having a'pair of normally open contact points 16. The field coil of this relay is in series as at 11 with the high voltagepositive plate supply to the plate of a suitable type vof actuating tube. The grid of this tube is connected at 'i9 to the plate of the last amplifier tube `of the recorder amplifier (not shown) with a blocking condenser 80 being placed in series in vthe lead 'I9 to isolate the grid from a direct connection with the positive current going to the plate of said amplier tube. Relay 15 is further in series at 'I8 with the grid of the illustrate GSJ'? tube. f

Relay 3l as beforementioned has correspondencewith `the relay 19 of Fig. 1 and is a-slow acting relay that is activated following a predetermined period of time after an electrical circuit is completed to and. through its ield winding. Such an electrical circuit is completed by the closing of the normally open contacts 16 operated by relay I5, relay 8l being connected in series with said contacts. When relay Si is finally activated after said pre-determined period of time, it operates to close its contacts 82, that which the relay 'l is located. As a result, after all sound impulses in either direction have been i terminated, said sound controlled relay would operate to open the circuit including relay'10, thus to de-energize the relay 10, causing contacts T3 to revert to closed position, thus to close a circuit to the cut off relay 69 which in turn would open the contacts 63 and open all other circuits.

An alternative connection can be that shown in Figure 2, wherein the relay 10 is adapted to be controlled by an electrical timing device, Anot shown. In this arrangement, leads 'H and 112 would not lead to the leads 28 and 6. Rather, they would be connected electrically tofan electrical timing device set into motion by beginning of the stabilized sustaining current in the telephone circuit. When said timing device has operated for a predetermined and preset time interval, it could close a circuit through relay 10, which would then close the normally open contacts 14, thus to energize the cut off relay B9.

It is to be understood that the apparatus is of course not limited to use With alternating current. Direct current operation can be provided for by eliminating power transformer I1; connecting leads c3 and i8 to one side of a local direct current supply; connecting leads 49 and l5 to the other side; and providing a switch in one side of said supply to perform the same function as switch I6 does when the apparatus is operated by alternating current as shown in the present drawing.

Figure 3 illustrates the sound controlled relay hereinbefore discussed, which relay is controlled by sound impulses formed in the circuit as long as a message is being either delivered to or given by the recording device.

To this end, I provide a voice-controlled relay and connections thereof tothe control circuit of 4the device wherein a relay lisanalogous to the relay 'l0 of Figs. 1 and 2,' andwhereinthe vcontacts 82 are analogous to the contacts 'I3 of lFig. 1

have correspondence with the contacts I3 of Fig. 1 and are connected in series in the lead ET. Thus, at such time as the contacts 82 close, a circuit is completed to relay 69 of Fig. l, opening the contacts S3 and causing reversion of all circuits to their normal or inoperative conditions, awaiting the next call to the instrument.

By means of a lead 83, the slow acting relay 3i and normally open contacts 'i6 are connected in series to a lead Bil. extending to the lead I9 to the secondary winding of power transformer ll. They are also connected, by means of lead 85, to a lead 86 extending to the lead E8 of Fig. 1.

In operation, the voice-controlled relay cuton" functions as follows: When the telephone ringing current activates the main circuit, the relay contact points 33 close after a short delay. This completes the circuit to the lament 'of the villustrated tube controlling the voice relay, since lead 86 extends from lead 68 that is connected to said contact points 38. As soon as the tube ywarms up properly, current begins flowing through the rleld coil of the relay 'l5 which is connected in series between the plate of the tube and the high voltage plate supply, there being -a lead 8T extending from said relay 'l5 to the plus or minus 250 volt plate supply of the recorder amplifier.

Since the grid of the tube is connected through a blocking condenser with the plate of the recorder amplier tube, any sound impulses being handled by that amplier will in turn be impressed. into the tube controlling the voice relay. These impulses result in an exceedingly rapid variation in the voltage of the current iiowing between the plate of that tube, the held winding of relay I5, and the high voltage plate supply. This .voltage reduction in the field winding of relay .IE5 causes its normally open contacts l to make and break contact intermittently, that is, each sound impulse impressed into the tube causes the contacts to return to their normally open po- With relay 'l5 opening and closing its contacts A'intermittently as soundimpulsesare impressed into the actuating tube, the electrical circuit through the' eld winding of slow acting relay 8L 4'contacts of relay 15 will be held in the closed vposition, the electrical circuit through the eld A'winding of relay 8| will be held in a completed condition, and the contacts 82 of relay Bl will close after a pre-set period of time.

With the closing of contacts 82, the electrical 'circuit to and through the eld winding of cut- -off relay 69 is completed. Contacts 63 are thus opened causing a reversion of all circuits to their normal or inoperative conditions awaiting the l'next use of the device.

Whatis claimed is: l. Electrical apparatus for receiving and. delivering telephone messages comprising `a starting switch; means connected conductively to a telephone circuit for closing said switch momentarily responsive to ringing current impressed on said circuit; a power circuit including and momentarily closed by said switch; a holding relay in the power circuit and holding the power circuit closed, after opening of said switch; a secondary circuit, closed by said relay; recorder input and output circuits connected to the telephone circuit by said relay; means in the secondary circuit for closing the recorder output and input circuits in turn for successive delivery and recording of messages.; a normally closed turn-Gif switch in the power circuit; a relay connected to the secondary circuit and opening said turn-off switch when activated; and means controlled by sound impulses travelling to and from said recorder input and output circuits and activating said relay on cessation of said impulses.

2. Electrical apparatus for receiving and delivering telephone messages comprising a starting switch; means connected conductively to a telephone circuit for closing said switch momentarily responsive to ringing current impressed on said circuit, a power circuit including and momentarily closed by said switch; a holding relay in the power circuit; a coupling transformer; a set of switches closed by the holding relay one of 'which by-passes the starting switch to hold the power circuit closed, the remaining switches of said set connecting one eld winding of the transformer to the telephone circuit; a secondary circuit closed by said relay; recorder input and output circuits connected to the other field winding of the transformer; means inthe secondary circuit for closing the recorder output vand input circuits in turn for successive delivery and recording of messages; a normally closed turn-off switch in the power circuit; a relay connected to the secondary circuit and opening said turn-01T switch when activated; and means controlled by sound impulses travelling to and from said recorder input and output circuits and activating said relay on cessation of said impulses.

3. Electrical apparatus for receiving and delivering telephone messages comprising a starting switch; a starting relay connected conduc- Ytively to a telephone circuit for energizaticn by intermittent ringing current impressed on said circuit to close said switch momentarily; a power circuit including and momentarily closed by said switch; a holding relay in the power circuit; a coupling transformer; a set of switches closed by the holding relay one of which by-passes the starter switch to hold the power circuit closed and the rest of which connect one eld winding yof the transformer conductively to the telephone relay; a delayed action relay in the secondary circuit; contacts closed by the delayed action relay; recorder input and output circuits connected to the other field winding of the transformer; means operable by closing of said contacts for closing the output and input circuits in turn, for successive delivering and receipt of messages; a normally closed turn-off switch in the power circuit; a relay `connected to the secondary circuit and opening said turn-off switch when activated; and means controlled by sound impulses travelling `to and from said recorder input and output circuits and activating said relay on cessation of said impulses.

4. Electrical apparatus for receiving and, delivering telephone messages comprising a power circuit including a source of electricity; means connected conductively to a telephone circuit and adapted to cause the power circuit to be closed momentarily responsive to intermittent ringing current impressed on the telephone circuit; means for holding the power circuit closed;

a secondary circuit; means in the power circuit for closing the secondary circuit; a de.ayed action relay in the secondary circuit; contacts closed by the delayed action relay; recorder input .and output circuits, connected to the telephone circuit; means operable by closing of said contacts for closing the output and input circuits in turn for delivery and receipt of messages; a turn-off control relay in the secondary circuit; a normally closed turn-01T switch in the power circuit; .a relay connected to the secondary circuit and opening said Vturn-olf switch when activated; and means controlled by sound impulses 'travelling to and from said recorder input and output circuits and activating said relay on cessation of said impulses.

5. Electrical apparatus for delivering and receiving telephone messages comprising ,a power circuit; means operable responsive to signal surges sent vthrough a telephone circuit to close and hold closed said power circuit; a secondary circuit; means in the power circuit for closing the secondary circuit; a delayed action relay in the secondary circuit; contacts closed by the delayed action relay; recorder input and output circuits, connected to the telephone circuit; means operable by closing of said contacts for closing the output and input circuits in turn for delivery and receipt of messages; a normally closed turn-ofi switch in the power circuit; a relay connected to the secondary circuit and opening said turn-.off switch when activated; and means controlled by sound impulses travelling to and from said recorder input and output circuits and activating said relay on cessation of said impulses.

6. Electrical apparatus for delivering and receiving telephone messages comprising a power circuit; means operable responsive to signal surges sent through a telephone circuit to close said power circuit; a holding relay in the power circuit; a-coupling transformer; a set of switches closed by the relay one of which by-passes Vsaid means to yhold the power circuit closed and the rest of which connect one field winding conductively to the telephone circuit; a secondary circuit closedby the holding relay; a delayed action relay in the secondary circuit; contacts closed by the delayed action relay; recorder input and output circuits connected to the other held winding of the transformer; means operable by closingfof said contacts for closing the output and input circuits, in turn, for successive delivering intermittent ringing current impressed on said' circuit to close said switch momentarily; a power circuit including and momentarily closed by said switch; a holding relay in the power circuit; a coupling transformer; a set of switches closed by the holding relay one of which by-passes the starter switch to hold the power circuit closed and the rest of which connect one eld winding of the transformer conductively to the telephone circuit; a secondary circuit closed by the holding relay; a delayed action relay in the secondary circuit; contacts closed by the delayed action relay; recorder input and output circuits connected to the other eld winding of the transformer; means operable by closing of said contacts for closing the output and input circuits in turn, for successive delivering and receipt of messages; a normally closed switch in the power circuit; a relay connected to the secondary circuit and opening said turn-off switch when activated; and means controlled by sound impulses travelling to and from said recorder input and output circuits and activating said relay on cessation of said impulses.

DONALD C. BEATTY.

REFERENCES CITED UNITED STATES PATENTS Name Date Keiser June 25, 1935 Number 

